Carpal Tunnel Release: Open Versus Endoscopic

The development of arthroscopic surgery has been one of the most significant advances in medical care this century. One hundred years ago a torn meniscus in the knee was a crippling injury resulting in intermittent knee pain, buckling and dysfunction with no prospect of successful treatment. Fifty years ago a torn rotator cuff meant a future of shoulder pain and weakness. Today an arthroscopic treatment can mean a relatively prompt return to activities and predictable relief of pain.

What about carpal tunnel surgery? Surgical release of the carpal tunnel is a relatively new procedure and was developed in the 1950s. Initially, patients were admitted for their surgery one day in advance and stayed in the hospital for two days afterwards; now the procedure is done under local anesthetic as an outpatient. Previously, patients were casted for two weeks; now patients are encouraged to use their hand and fingers immediately.

Is the use of an endoscope to perform the surgery the next advance in surgical treatment of carpal tunnel syndrome? Perhaps, but perhaps not.

There are many effective surgical treatments for carpal tunnel syndrome, but all currently accepted methods involve cutting the transverse carpal ligament which compresses the median nerve. The two primary ways of exposing that ligament and releasing it are (1) through an open incision or (2) endoscopically. There are multiple variations of each method, but all surgeries will fall into one camp or the other. The essential part of the surgical treatment, transection of the compressing ligament, is the same in both procedures; all that differs is the surgical exposure of the ligament.

Most surgeons will prefer either open or endoscopic release, and most surgeons are trained in both procedures. There is no consensus regarding which procedure is preferable. I personally prefer an open release, but I am trained in, and experienced in, endoscopic release. In fact, I performed the first endoscopic carpal tunnel release in the United States Navy during my time in Desert Storm while I was stationed in San Diego. The procedure is valid and effective, but I prefer an open release because I think it is safer, more effective, safer, more cost efficient, and safer.

What does the literature say?:

“Systematic review of randomized clinical trials of surgical treatment for carpal tunnel syndrome.” British Journal of Surgery, 2001: endoscopic CTR and open CTR are equally effective.

“A meta-analysis of randomized controlled trials comparing endoscopic and open carpal tunnel decompression.” Plastic Reconstructive Surgery, 2004: endoscopic CTR provides a quicker return of strength and less scar tenderness, but there is a 300% greater chance of nerve injury.

“CTS treatment guideline: American Academy of Orthopaedic Surgeons, 2008: both methods are effective.

“Complications of open and endoscopic carpal tunnel release.” Arthroscopy, 2006: complication rate low in both, but incidence of digital nerve injury was ten times higher in the endoscopic release group (0.03% vs 0.39%)

One of the primary duties of a surgeon is to avoid unnecessary risk. All studies show that the long term outcomes of open versus endoscopic carpal tunnel release are equal. The primary benefit of endoscopic release is less pain and tenderness in the few weeks after the procedure. Since the risk of nerve injury is significantly higher with endoscopic release, and the risk of incomplete release of the ligament is also higher, there would need to be a significant long-term benefit to the procedure to outweigh this greater risk. There is not, and that is why I prefer an open release of the carpal tunnel.